Method, system, and computer readable storage medium for controlling engine starts

ABSTRACT

Systems, methods, and computer readable storage media are described for a vehicle, such as a locomotive. In one example, a system comprises an automatic engine start/stop control system configured to automatically start the engine at a selected clock time.

FIELD

The subject matter disclosed herein relates to a method, system, andcomputer readable storage medium for automatically starting an engine ina vehicle, such as a locomotive.

BACKGROUND

Locomotives may be operated to provide scheduled services wherein theyare scheduled to depart at a fixed time and/or at fixed time intervals.Accordingly, a locomotive engine and associated electronic systems arestarted in advance of the scheduled time of departure to enable acomprehensive check of engine and system operational parameters, and toenable the locomotive to be prepared and/or positioned for service.

In one example, commuter trains are often scheduled to start at earlymorning hours. Consequently, service personnel are required to arrive ata train yard significantly earlier in order to monitor and start theengine of the locomotives parked at the yard and initiate preparationprocedures. The use of human intervention in the management of alocomotive engine and associated engine control systems may therebyintroduce unwanted errors and delays that may adversely affect theability of the locomotive to depart at the stipulated time, and mayincrease overall operation costs.

BRIEF DESCRIPTION OF THE INVENTION

Methods, systems, and computer readable media are provided forautomatically starting an internal combustion engine in a vehicle, suchas a locomotive, at a desired time and/or after a desired time interval.In one embodiment, a system comprises an automatic engine start/stopcontrol system configured to automatically start the engine at aselected clock time. For example, the engine can be automaticallystarted at the appropriate time to improve adherence to operatingschedules, without requiring human intervention.

In another embodiment, a method of automatically starting an engine of alocomotive operating on a schedule comprises: during locomotiveshut-down conditions, monitoring a locomotive operating parameter, andautomatically starting the engine when a locomotive operating parameterfalls outside a desired condition, and then stopping the engine when thelocomotive operating parameter regains its desired condition. Further,at a selected clock time, and if the engine is currently stopped, themethod includes starting the engine, and then maintaining the engineoperating for at least a selected duration, independent of thelocomotive operating parameter. Alternatively, at the selected clocktime, and if the engine is currently running, the method includesmaintaining the engine operating for at least the selected duration,independent of the locomotive operating parameter. In this way, theautomatic engine starting used to maintain operating parameters withindesired conditions can be coordinated with the clock-scheduled automaticstarting. In still another embodiment, a computer readable storagemedium of a locomotive control system may be programmed with code toperform various operations, such as those noted above.

It should be understood that the summary above is provided to introducein simplified form a selection of concepts that are further described inthe detailed description. It is not meant to identify key or essentialfeatures of the claimed subject matter, the scope of which is defineduniquely by the claims that follow the detailed description.Furthermore, the claimed subject matter is not limited toimplementations that solve any disadvantages noted above or in any partof this disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood from reading thefollowing description of non-limiting embodiments, with reference to theattached drawings, wherein below:

FIG. 1 shows an example embodiment of a diesel-electric locomotive.

FIG. 2 shows a high level flow chart for a system configured toautomatically start/stop an engine.

FIG. 3 shows a high level flow chart for a system configured with analarm clock and/or sleeper function, according to the presentdisclosure.

DETAILED DESCRIPTION

Locomotives, or other vehicles, may be configured with integratedlocomotive control systems that improve operation efficiency andfacilitate fleet management. One example of such a configuration isillustrated with reference to FIG. 1 wherein an Automatic EngineStart/Stop control system (AESS) monitors locomotive operatingparameters, irrespective of whether the engine is running or stopped.The AESS may estimate the locomotive operating parameters and thenevaluate them against desired operating conditions. Further, aselaborated in FIG. 2, the AESS may automatically start or stop an idlelocomotive, as conditions warrant, without an operator triggered cue.Alternatively, the AESS may receive operator-triggered cues for enginestart-up and/or shut-down. The AESS may be further coordinated with aclock function to perform a clock-scheduled auto-start, as elaborated inFIG. 3, based on the operating schedule of the locomotive. As such,locomotives operating with such integrated control systems may achieveimproved fuel efficiency, consistent performance, timely departures andoverall reduced operation costs.

FIG. 1 is a block diagram of an example vehicle system for a locomotive100, configured to run on track 104. As depicted herein, in one example,the locomotive is a diesel electric vehicle operating a diesel engine106 located within a main engine housing 102. However, in alternateembodiments of locomotive 100, alternate engine configurations may beemployed, such as a gasoline engine or a biodiesel or natural gasengine, for example.

Locomotive operating crew and electronic components involved inlocomotive systems control and management, for example controller 110,may be housed within a locomotive cab 108. In one example, controller110 may include a computer control system. The locomotive control systemmay further comprise computer readable storage media including code forenabling an on-board monitoring of locomotive operation. Controller 110,overseeing locomotive systems control and management, may be configuredto receive signals from a variety of sources in order to estimatelocomotive operating parameters. Controller 110 may be further linked toa display 112, such as a diagnostic interface display, providing a userinterface to the locomotive operating crew. Controller 110 may also beconfigured to operate an automatic engine start/stop control system onan idle locomotive 100, thereby enabling the locomotive engine to beautomatically started and stopped upon fulfillment of AESS criteria.Alternatively, an operator may manually indicate an intention to motorthe locomotive by moving a direction controller, herein depicted byreverser 114.

Engine 106 may be started with an engine starting system. In oneexample, a generator start may be performed wherein the electricalenergy produced by a generator or alternator 116 may be used to startengine 106. Alternatively, the engine starting system may comprise amotor, such as an electric starter motor, or a compressed air motor, forexample. It will also be appreciated that the engine may be startedusing energy in a battery system, or other appropriate energy sources.

The diesel engine 106 generates a torque that is transmitted to analternator 116 along a drive shaft (not shown). The generated torque isused by alternator 116 to generate electricity for subsequentpropagation of the vehicle. Locomotive engine 106 may be run at aconstant speed, thereby generating a constant horsepower output, or atvariable speed generating variable horse power output, based onoperational demand. The electrical power generated in this manner may bereferred to as the prime mover power. The electrical power may betransmitted along an electrical bus 117 to a variety of downstreamelectrical components. Based on the nature of the generated electricaloutput, the electrical bus may be a direct current (DC) bus (asdepicted) or an alternating current (AC) bus.

Alternator 116 may be connected in series to one, or more, rectifiers(not shown) that convert the alternator's electrical output to DCelectrical power prior to transmission along the DC bus 117. Based onthe configuration of a downstream electrical component receiving powerfrom the DC bus, one or more inverters 118 may be configured to invertthe electrical power from the electrical bus prior to supplyingelectrical power to the downstream component. In one embodiment oflocomotive 100, a single inverter 118 may supply AC electrical powerfrom a DC electrical bus to a plurality of components. In an alternateembodiment, each of a plurality of distinct inverters may supplyelectrical power to a distinct component. It will be appreciated that inalternative embodiments, the locomotive may include one or moreinverters connected to a switch that may be controlled to selectivelyprovide electrical power to different components connected to theswitch.

A traction motor 120, mounted on a truck 122 below the main enginehousing 102, may receive electrical power from alternator 116 via the DCbus 117 to provide traction power to propel the locomotive. As describedherein, traction motor 120 may be an AC motor. Accordingly, an inverterpaired with the traction motor may convert the DC input to anappropriate AC input, such as a three-phase AC input, for subsequent useby the traction motor. In alternate embodiments, traction motor 120 maybe a DC motor directly employing the output of the alternator 116 afterrectification and transmission along the DC bus 117. One examplelocomotive configuration includes one inverter/traction motor pair perwheel-axle 124. As depicted herein, six pairs of inverter/tractionmotors are shown for each of six pairs of wheel-axle of the locomotive.In alternate embodiments, locomotive 100 may be configured with fourinverter/traction motor pairs, for example. It will be appreciated thatin alternative embodiments, a single inverter may be paired with aplurality of traction motors. Traction motor 120 may also be configuredto act as a generator providing dynamic braking to brake locomotive 100.In particular, during dynamic braking, the traction motor may providetorque in a direction that is opposite from the rolling directionthereby generating electricity that is dissipated as heat by a grid ofresistors 126 connected to the electrical bus. In one example, the gridincludes stacks of resistive elements connected in series directly tothe electrical bus. The stacks of resistive elements may be positionedproximate to the ceiling of main engine housing 102 in order tofacilitate air cooling and heat dissipation from the grid.

Air brakes (not shown) making use of compressed air may be used bylocomotive 100 as part of a vehicle braking system. The compressed airmay be generated from intake air by compressor 128.

A multitude of motor driven airflow devices may be operated fortemperature control of locomotive components. The airflow devices mayinclude, but are not limited to, blowers, radiators, and fans. A varietyof blowers 130 may be provided for the forced-air cooling of variouselectrical components. For example, a traction motor blower to cooltraction motor 120 during periods of heavy work, an alternator blower tocool alternator 116 and a grid blower to cool the grid of resistors 126.Each blower may be driven by an AC or DC motor and accordingly may beconfigured to receive electrical power from DC bus 117 by way of arespective inverter.

Engine temperature is maintained in part by a radiator 132. Water may becirculated around engine 106 to absorb excess heat and contain thetemperature within a desired range for efficient engine operation. Theheated water may then be passed through radiator 132 wherein air blownthrough the radiator fan may cool the heated water. The radiator fan maybe located in a horizontal configuration proximate to the rear ceilingof locomotive 100 such that upon blade rotation, air may be sucked frombelow and exhausted. A cooling system comprising a water-based coolantmay optionally be used in conjunction with the radiator 132 to provideadditional cooling of the engine.

An on-board electrical energy storage device, represented by battery 134in this example, may also be linked to DC bus 117. A DC-DC converter(not shown) may be configured between DC bus 117 and battery 134 toallow the high voltage of the DC bus (for example in the range of 1000V)to be stepped down appropriately for use by the battery (for example inthe range of 12-75V). In the case of a hybrid locomotive, the on-boardelectrical energy storage device may be in the form of high voltagebatteries, such that the placement of an intermediate DC-DC convertermay not be necessitated. The battery may be charged by running engine106. The electrical energy stored in the battery may be used during astand-by mode of engine operation, or when the engine is shut down, tooperate various electronic components such as lights, on-boardmonitoring systems, microprocessors, processor displays, climatecontrols, and the like. Battery 134 may also be used to provide aninitial charge to start-up engine 106 from a shut-down condition. Inalternate embodiments, electrical energy storage device 134 may be asuper-capacitor, for example.

Controller 110 may control the engine 106, in response to AESSinstructions, by sending a command to the gamut of engine controlhardware components such as invertors 118, relays (not shown),alternator 116, fuel pumps (not shown), etc. Controller 110 may monitorlocomotive operating parameters in idle locomotive 100, operating in astand-by mode or shut-down mode. Upon verifying that AESS criteria aremet, a computer readable storage medium configured in controller 110 mayexecute code to appropriately auto-stop or auto-start engine 106 byenabling performance of an AESS routine, as further elaborated below inFIG. 2. Further, if it is desired to auto-start locomotive 100 from ashut-down mode at a preset time, or after a preset time interval, thedesired settings may be incorporated into the AESS routine of FIG. 2.Accordingly, by performing an alarm clock/sleeper routine, as furtherelaborated in FIG. 3, the AESS may be configured to automatically startthe engine at a selected clock time.

FIG. 2 depicts an AESS routine 200 that may be performed by controller110 during a stand-by or shut-down mode of locomotive operation. In oneexample, the locomotive may be in a stand-by mode when parked on asiding for a long term with the engine running at an idling speed, and acomputer control system of the locomotive maintained active. In anotherexample, locomotive 100 may be shifted to a stand-by mode after 4000hours of engine operation. In the shut-down mode, locomotive 100 may bestationary and parked, and further the engine may not be running.However, on-board electronics, such as an on-board locomotive monitoringsystem, or a computer control system of the locomotive are maintainedactive during the shut-down conditions. The AESS routine 200 may allowmonitoring of a plurality of locomotive operating parameters to verifythat they are at a desired condition. If the AESS criteria are met, andthe engine is running, the engine may then be automatically shut-down.In this way, by reducing the idling time of the locomotive engine 106,fuel economy and reduced emission benefits may be achieved. In contrast,during locomotive shut-down conditions, a plurality of engine operatingparameters may be monitored and further, the engine may be automaticallystarted in response to any of the plurality of monitored locomotiveoperating conditions falling outside a respective desired condition. Theengine may be stopped when the operating condition regains the desiredcondition. By maintaining the locomotive operating parameters in anoperation ready-state at all times, locomotive efficiency may beimproved.

Routine 200 may include, at 202, monitoring locomotive operatingparameters and determining whether they are at a desired condition, suchas within a desired range of values or above a desired threshold value.The parameters monitored may include, for example, ambient temperature,engine oil temperature, compressor air pressure, main air reservepressure, battery voltage, a battery state of charge and brake cylinderpressure. In one example, only one of the plurality of locomotiveoperating parameters may be monitored and used to determine if AESScriteria are met. In another example, some or all of the locomotiveoperating parameters may be concurrently monitored and used to determineif AESS criteria are met. Upon estimating the conditions and verifyingtheir values against a prescribed range of desired values, at 204 and206, it is determined whether the engine is currently running.

If the locomotive operating parameter(s) are at the desired condition,and the engine is not currently running, that is the locomotive is in ashut-down mode, then at 208, the locomotive engine may be maintained ina shut-down mode. However, if the parameters are within range and theengine is currently running, that is the locomotive is in a stand-bymode, the engine may be automatically shut-down, or auto-stopped, at210. At 212, controller 110 may check the alarm clock and sleeperfunction of the AESS to determine if a selected clock time for enginestart has been indicated by the operator. Accordingly, an alarmclock/sleeper routine 300, as further elaborated in FIG. 3, may beperformed wherein the automatic engine start/stop control system may beconfigured to automatically start the engine at a selected clock time.

If the parameters are not within range, and the engine is currentlyrunning, then at 214, the engine may be kept running to allow theparameters to be brought back to the desired condition. If any of theplurality of monitored locomotive operating parameters falls outsidetheir respective desired condition, and further if the engine is notcurrently running, then at 216, the engine may be automatically startedto enable the desired conditions to be regained. It will be appreciatedthat in alternate examples, the engine may be automatically started whenany of the monitored locomotive operating parameters fall outside theirrespective desired conditions. In one example, if the battery charge hasdissipated and consequently the battery state of charge has dropped,then the engine may be run to allow the electrical power generated bythe engine to be used to recharge the battery and regain a desiredbattery state of charge. In another example, if the compressor airpressure has fallen below a desired value, then the engine may be rununtil the compressor is sufficiently full of compressed air and acompressed air storage pressure has been reached. It will be furtherappreciated that the threshold of a locomotive operating parameter atwhich the engine is automatically started may differ from the thresholdat which the engine is automatically shut-down. In one example, theengine may be automatically started when the battery state of charge hasdropped below 30%. In contrast, the engine may be run until a batterystate of charge of 50% is reached, following which the engine may beautomatically shut-down.

Subsequently, at 218, the controller may read the alarm clock andsleeper functions of the AESS to determine if a selected clock time hasbeen indicated by the operator. Accordingly, controller 110 may performalarm clock/sleeper routine 300 to determine if the engine should bekept running or auto-stopped. In this way, an automatic enginestart/stop control system may be configured to monitor locomotiveoperating parameters during a locomotive stand-by and/or shut-down mode,and automatically start the engine when a locomotive operating parameterfalls outside a desired condition, and then stop the engine when theoperating condition regains its desired condition.

FIG. 3 depicts an alarm clock/sleeper routine 300 that may beincorporated into an AESS system in one embodiment. The routine allows alocomotive in a shut-down condition to be auto-started at a desired timepoint, based on the departure schedule of the locomotive. The selectedclock time may be an absolute clock time or a relative clock time. Thespecified “wake-up time” and/or “sleep time” may be communicated to theAESS by an operator via display 112. In alternate embodiments, forexample when a display is not available, the alarm clock/sleeperconfigurations may be communicated via programmable settings in thealarm clock/sleeper code. Upon starting the engine, an associated enginecontrol system may monitor locomotive operating parameters and performappropriate adjustments such that the locomotive engine may be in anoperation-ready state at the desired time point. Consequently, thelocomotive may be operated on demand from an operator without therequirement for prior maintenance procedures by service personnel.

In one example, if stationary locomotive 100 is scheduled to depart at 6a.m., the AESS system may be configured with a selected clock timewherein the selected clock time includes an absolute clock time.Accordingly, at 5 a.m., the selected “wake-up time” for example,controller 110 may auto-start engine 106 and perform a maintenanceroutine on system components to verify AESS criteria are met, such as acompressor air pressure, a battery voltage, a battery state of charge,an engine temperature, etc. are within a desired range. Followingmaintenance procedures, controller 110 may prevent the engine 106 frombeing auto-stopped for a preselected duration and instead allowlocomotive 100 to be kept in an idle state until the operating crewarrive and proceed to operate the locomotive.

In another example, if it is desired to auto-start the engine 106 afterbeing parked in the yard for 10 hours, the AESS system may be configuredwith a selected clock time wherein the selected clock time includes arelative clock time. Further, the selected (relative) clock time may bea time interval, e.g. 10 hours, from a previous shut-down. As such, theAESS may indicate a selected “wake-up time” to be calculated based on aspecified “sleep time” of 10 hours. Accordingly, 10 hours after aprevious shut-down, controller 110 may auto-start engine 106, performmaintenance routines, and allow locomotive 100 to be kept in an idlestate until the arrival of the operating crew. In this way, byincorporating time element features into an automatic engine start/stopsystem, and by performing routine 300, as elaborated below in FIG. 3, acontrol system for a locomotive operating on a schedule automaticallystarts the engine at the selected clock time while the vehicle isstationary. It will be appreciated that while the engine may not berunning, the AESS maintains a computer control system of the locomotiveactive during the shut-down conditions. Alternatively, such operationmay be used on towed locomotives in a shut-down or stand-by mode.Additionally, or optionally, operation of the AESS system may besuspended between the “wake-up time” and the “sleep time”.

At 302, the controller 110 reads a selected clock time. The selectedclock time may be represented by a “wake-up time” specified on the alarmclock function or a “sleep time” interval specified on the sleeperfunction. The selected clock time may be adjusted based on a variety ofschedule related parameters. In one aspect, the selected clock time isbased on a calendar date and further based on whether the calendar dateis a weekday or a weekend. In one example, the selected clock time maybe input in a 5-1-1 week configuration wherein the clock time isadjusted based on whether it is one of the 5 weekdays, or whether it isa Saturday, or a Sunday. As such, in the 5-1-1 configuration, thelocomotive may be auto-started at an earlier time, or after a shorterinterval on weekdays and at a later time, or after a longer interval, onSaturdays and Sundays, based on the difference in schedule of thelocomotive on a weekday versus a weekend day. It will be appreciatedthat in an alternate aspect, the selected clock time may be furtheradjusted depending on the day of the week. For example, the selectedclock time may be earlier on a Monday and later on a Wednesday.

In another aspect, the selected clock time is based on whether thecalendar date is a holiday whereon the locomotive may operate on aholiday schedule. In still another aspect, the selected time is adjusteddepending on a calendar day. In one example, the day may be a day onwhich a time zone time is adjusted. Accordingly, the selected time maybe adjusted to reflect the appropriate time in that time zone, such as adaylight saving time. In yet another aspect, the selected time may be atime interval from a previous shut-down of the locomotive. In this way,the selected time may be adjusted based on a calendar schedule to matchthe operation schedule of the locomotive 100.

At 304, the routine counts down the amount of time remaining until thespecified “wake-up time”, and/or the end of the specified “sleep time”interval. An indication of the amount of time that has elapsed and/orthe amount of time remaining in the countdown may be displayed ondisplay 112 to notify the operator of the engine status. By specifying atime at when auto-start is desired, the engine may be maintained in ashut-down mode until the engine is required to be running, therebyreducing unwanted fuel usage and NOx emissions.

The engine may continue to remain in a shut-down mode of operation untilthe selected clock time unless prompted to start by alternate cues. At306, routine 300 determines if an operator-triggered auto-startindication has been provided. The operator-triggered auto-startindication may be provided by the operator to indicate a suddenintention to motor and propel the locomotive. In one example, anoperator-triggered auto-start may be indicated by the operator movingthe reverser 114 from a center (“neutral”) position. In another example,a manual start may be indicated by an operator communicating anauto-start on the AESS system. Upon receiving an operator-triggeredauto-start indication, at 308 the controller 110 may abort automaticallystarting the engine at the selected absolute or relative clock time, inanticipation of an imminent locomotive motion.

If at 306, an operator-triggered auto-start is not indicated, then at310 the routine may verify if AESS criteria are met. That is, one or aplurality of locomotive operating parameters may be monitored, as inroutine 200 (FIG. 2). The locomotive operating parameters may includecompressor air pressure, brake cylinder air pressure and a battery stateof charge for example, and verification that they are within a desiredrange. If a locomotive operating parameter falls outside the respectivedesired range, this may be perceived as an alternate auto-start cue.Accordingly, at 312, the AESS automatically starts the engine inresponse to an operating parameter falling outside a desired range anduses the electrical power generated by running engine 106 to return theparameter to within the desired range. In one example, if the brakecylinder pressure is determined to have fallen below a prescribedminimum threshold, then at 312, the engine may be auto-started to allowthe compressor to compress air and raise the brake cylinder pressure.

If no operator-triggered auto-start is indicated at 306, and further ifthe locomotive operating parameters are within the desired range, at314, routine 300 may continue counting down to the selected clock timeand auto-start the engine 106 at the predefined “wake-up time”. In thisway, a control system may automatically start the engine of a vehicle,such as a locomotive operating on a schedule, at a selected clock timebased on the locomotive operating schedule, and while the vehicle isstationary. By performing a comprehensive check of engine components andoperating parameters before starting the engine at a specified “wake-uptime”, based on the selected clock time, a locomotive engine may be keptin an operation-ready state such that the locomotive may be propelledupon operator demand. Given that the engine may be started automaticallyat the selected clock time without operator or service personnelintervention, the possibility of human factor related delays and errorsin locomotive operation may be reduced.

At 316, an auxiliary snooze attribute of the alarm clock/sleeperfunction configured on the AESS may be estimated. The “snooze” functionmay enable the automatic engine start/stop control system to maintainthe engine operating for a selected duration after the automatic start,independent from the operating parameter, and then shut down the engine,thereby averting premature engine shut-down. If a desire to “snooze” hasbeen indicated to the controller 110, then a specified “snooze_time” maybe noted and at 318, the controller may not allow the engine to beauto-stopped for the duration of the “snooze_time”. For example, theAESS may maintain the engine operating for the preselected durationafter the automatic start, independent from the operating parameter, andthen later shut down the engine. In one embodiment, when in the snoozemode, at 320, the controller may be directed to display a “snooze-time”indicator, for example on the display 112, for the duration of the“snooze_time”. This may allow the operator to be notified of theoperating snooze mode and may further indicate that at the end of thesnoozing period, the engine may be idled for a required amount of time(“required_idle_time”) and then auto-stopped. To further notify theoperator of the imminent auto-stop, at 322, the “snooze time” indicationmay be switched to an “auto stop pending” indication, for example on thedisplay, after a time:

t=“snooze_time”−“required idle_time”

During this time, the display may further indicate a countdown (of thesnooze interval) to auto-stop. In one example, the operator may note theindication of the end of the snooze mode and may opt to change AESSsettings to prevent the pending auto-stop and instead may manuallyindicate (for example by changing the reverser 114 position) a desire topropel the locomotive immediately. If no snooze was desired at 316, theroutine may end. In this way, routine engine assessments and engineoperation may be performed responsive to a desired locomotive operatingschedule, thereby reducing human intervention in engine control, andconsequently, the possibility of human factor related delays and errorsin locomotive operation.

It will be appreciated that in an alternate embodiment, the operationsas described in FIGS. 2-3, may be executed by programmable codeconfigured on computer readable storage media of a locomotive controlsystem. In one example, the computer readable storage medium maycomprise code for, during a first locomotive condition where the engineis shut-down, monitoring a plurality of locomotive operating parameters,and automatically starting the engine when any of the plurality oflocomotive operating parameters falls outside respective desiredconditions, and then stopping the engine when all of the monitoredlocomotive operating parameters regain the respective desiredconditions. The computer readable storage medium may further comprisecode for, during a second locomotive condition where the engine isshut-down, automatically starting the engine at a selected absoluteclock time, or during a third locomotive condition where the engine isshut-down, automatically starting the engine at a selected relativeclock time based on a time interval from a previous engine shut-down.During any of the second and third conditions, programmable code mayfurther enable maintaining the engine running for at least a selectedduration after the start, independent of any locomotive operatingparameters. Further, the code may be programmed to execute, during afourth locomotive condition where the engine is running, maintaining theengine operating after the selected clock time (absolute or relative),such as for a selected duration.

A statistical analysis of locomotive usage may be provided to allow forimproved locomotive and fleet management. The computer readable storagemedium of controller 110 may be configured to comprise code for trackingand tabulating a frequency of automatically starting the engine at aselected absolute clock time or relative clock time, a frequency ofautomatically starting the engine when a locomotive operating parameterfalls outside a desired condition, and a frequency of automaticallystopping the engine when a locomotive operating parameter is within adesired condition. The analysis may further include statisticspertaining to the recurrence of operator-triggered auto-startindications. The analysis may also include the reason for automaticengine start/stop. In one example, if the statistics indicate thatlocomotive 100 was automatically started/stopped frequently due torecurring drops in compressor air pressure, a compressor componentdefect may be perceived and addressed accordingly. In another example,if the statistics indicate that locomotive 100 spent a significantamount of time in a snooze mode, the locomotive's operation schedule maybe rearranged within the fleet. In this way, system usage statistics andaverages, locomotive performance statistics and averages, and fleetstatistics and cumulatives may be computed. By providing a statisticalanalysis of the frequency of automatic engine start/stop and acompilation of time spent in the different modes (for e.g., stand-bymode, shut-down mode, snooze mode, suspend mode between “wake-up” and“sleep” times, etc.) may allow for statistical tracking of thelocomotive and consequently improved locomotive management.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and may include other examplesthat occur to those skilled in the art. Such other examples are intendedto be within the scope of the claims if they have structural elementsthat do not differ from the literal language of the claims, or if theyinclude equivalent structural elements with insubstantial differencesfrom the literal languages of the claims.

1. A system for a vehicle, comprising: an automatic engine start/stopcontrol system configured to automatically start the engine at aselected clock time.
 2. The system of claim 1 wherein the selected clocktime includes an absolute clock time.
 3. The system of claim 1 whereinthe selected clock time includes a relative clock time.
 4. The system ofclaim 1 wherein the vehicle is a locomotive operating on a schedule, andwhere the selected clock time is based on the locomotive operatingschedule, and where the control system automatically starts the engineat the selected clock time while the vehicle is stationary.
 5. Thesystem of claim 1 wherein the automatic engine start/stop control systemfurther starts the engine in response to an operating parameter fallingoutside a desired range.
 6. The system of claim 5 wherein the automaticengine start/stop control system maintains the engine operating for apreselected duration after the automatic start, independent from theoperating parameter, and then shuts down the engine.
 7. The system ofclaim 1 wherein the selected clock time is adjusted depending on acalendar day.
 8. The system of claim 7 wherein the selected clock timeis based on a calendar date, and further based on whether the calendardate is a weekday.
 9. The system of claim 8 wherein the selected clocktime is based on whether the calendar date is a holiday.
 10. A method ofautomatically starting an engine of a locomotive operating on aschedule, the method comprising: during locomotive shut-down conditions:monitoring a locomotive operating parameter, and automatically startingthe engine when the locomotive operating parameter falls outside adesired condition, and then stopping the engine when the locomotiveoperating parameter regains the desired condition; at a selected clocktime, and if the engine is currently stopped, starting the engine, andthen maintaining the engine operating for at least a selected duration,independent of the locomotive operating parameter; and at the selectedclock time, and if the engine is currently running, maintaining theengine operating for a least the selected duration, independent of thelocomotive operating parameter.
 11. The method of claim 10 wherein thelocomotive operating parameter includes a battery state of charge. 12.The method of claim 11 further comprising adjusting the selected clocktime based on a calendar date.
 13. The method of claim 12 furthercomprising maintaining a computer control system of the locomotiveactive during the shut-down conditions.
 14. The method of claim 11wherein the selected clock time is a time interval from a previousengine shut-down.
 15. The method of claim 11 wherein the selected clocktime is an absolute clock time.
 16. A computer readable storage mediumfor a locomotive control system, comprising: code for, during a firstlocomotive condition where the engine is shut-down, monitoring aplurality of locomotive operating parameters, and automatically startingthe engine when any of the plurality of monitored locomotive operatingparameters falls outside respective desired ranges, and then stoppingthe engine when all of the monitored locomotive operating parameter arewithin the respective desired ranges; code for, during a secondlocomotive condition where the engine is shut-down, automaticallystarting the engine at a selected absolute clock time; code for, duringa third locomotive condition where the engine is shut-down,automatically starting the engine at a selected relative clock time froma previous engine shut-down; and code for, during a fourth locomotivecondition where the engine is running, maintaining the engine operatingafter the selected absolute clock time or relative clock time.
 17. Themedium of claim 16 further comprising code for, during any of the secondand third locomotive conditions, maintaining the engine running for atleast a selected duration after the start.
 18. The medium of claim 16,wherein the code for maintaining includes code for maintaining theengine operating for a selected duration.
 19. The medium of claim 16further comprising code for receiving a locomotive operating schedule,the schedule varying depending on a calendar day.
 20. The medium ofclaim 16 further comprising code for, during any of the second and thirdlocomotive conditions, receiving an operator-triggered auto-startindication; and aborting automatically starting the engine at theselected absolute clock time or relative clock time.
 21. The medium ofclaim 20 wherein the indication is indicative of a locomotive operatorhaving repositioned a locomotive direction controller.
 22. The medium ofclaim 20 further comprising code for tracking a frequency ofautomatically starting the engine at a selected absolute clock time orrelative clock time, a frequency of automatically starting the enginewhen a locomotive operating parameter falls outside a desired condition,and a frequency of automatically stopping the engine when a locomotiveoperating parameter regains the desired condition.